A detector is known from EP 0 819 406 A1. The known detector is constructed from a number of modules both in the z-direction and in the φ-direction. This is a so-called multirow detector in which a number of rows of detector elements are arranged sequentially in the z-direction. This enables a number of images to be produced simultaneously in parallel sectional positions during a single measurement path.
In order to simplify the mounting, the detector elements are usually combined to form detector modules. In order to achieve the highest possible measuring accuracy, it is necessary for each detector module or collimator attached thereto on the beam input side to be aligned exactly with an X-ray machine arranged opposite the detector.
DE 101 58 021 A1 discloses a detector module that is composed of a collimator module and a sensor module. The detector module has lateral projections of opposing arrangement and with adjusting devices that cooperate with further adjusting devices, provided on a fastening frame, for accurately positioning the detector module on the frame. The proposed detector module is suitable for producing a detector in which in the z-direction only relatively few rows, that is to say four rows, are sequentially arranged.
DE 197 53 268 A1 describes a detector for an X-ray computed tomograph in which the collimator is designed in the form of thin metal plates that are mounted on a detector frame. An auxiliary device of comb-like design is provided for adjusting the metal plates.
In multirow detectors with a high number of rows, for example 16 rows, it has proved to be expedient in practice to attach a number of detector modules sequentially in the z-direction. It is necessary in this case to keep the interspaces between the detector modules as small as possible, in particular smaller than 300 μm. The accurate arrangement of such detector modules, and their precise adjustment to the focus of the X-ray machine require a relatively high outlay in practice.